Distributing gear for big hydraulic working machines



Dec. 30, 1930. E. SCHOTTLER 1,787,328

DISTRIBUTING GEAR FOR BIG HYDRAULIC WORKING MACHINES Filed Jan. 8, 19302 Sheets-Sheet l -n r Q 1 AW g @HIH M lNVENTOR ,EmiZ 5cm?" if %/%M za-252220 Dec. 30, 1930. E. SCHOTTLER DISTRIBUTING GEAR FOR BIG HYDRAULICWORKING MACHINES Filed Jan. 8, 1930 2 Sheets-Sheet 2 LUJULUJ l/VVE/VTQR.End SchbZZ'Zer.

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Patented Dec. 30, 1930 'EMIL SjCHT'ILER, OF 'ESSEN-RUTT, GERMANYDISTRIBUTING GEAR FOR BIG HYDRAULIC WORKING MACHINES Application filedJanuary 8, 1930, Serial No. 419,400, and in Germany March 2, 1927.

I have filed application for. patent in Germany on March 2nd, 1927, No.Sch. 81,895 XI/ and on December 7th, 1929, No. Sch. 92,451 VI/80 l andin France 011 December 4th, 1929, No. 285,990 of which the following isa specification.

he invention concerns a distributing gear for those hydraulic machines(cranes, presses, converter devices, etc.) in which the frictionalresistance in t e leathercups of the piston valve is so great thatdirect actuation of the distributing means is impossible and in whichlikewise the piston valve can be fixed in a central position,

In the known devicesof this kind a large auxiliary piston is-mountedloose on the p ston rod of the distributin slide valve and the auxiliarycylinder is deslgned as a stepped cylinder.

as a. piston in the auxiliary piston, and the pistons therefore owing totheir inaccessibility are very difficult to'keep, tight.

The invention aims at remedying this de-L' feet and creating a simplerarrangement 1n-.

auxiliary cylinder into the path of the pis-' ton valve. 1

On the drawing two.constructionalexamplesof the inventlonare sho wn indiagram, Figs. 1 .to 3 illustrating 1n longitudinal section threedifi'erent positions of a distrib- 5 utin gear for a hydraulic machinealways Wor ing with the same pressure of liguld. Fig. 4 is a sideelevation of a hy rauhc brickpress working with high and low pressurewith a longitudinal section through the distributing gear and 4 Figs. 5and 6 show thevdistributmg gear in two diflerent positions of the parts.

In a'longitudinal bore of the housing a which serves as distributingcylinder, there is guided a freely suspended piston valve b whichprojects by a prolongationI from the housing a. The pressure liquid islet in through the pipe 0 terminating 1n the upper ,end of the-housinga; the outflow Ofthe liquid is efiected through the opening d in The,drawback of this arrange- 20 ment is that the piston rod must also workcounter directed movement.

the housing a. The opening 0 provided a little below the mouth of theduct 0 is connected by a duct with the working cylinder (not shown). Theopening e has a branch 6 which ends in the 1011' itudinal bore of thehousing a at the level 0 the outflow opento the working cylinder. whilethe latter is in communication with the outlet d by 'way of the branch 6and the space between the two bottom parts of the piston. In the middleposition of the distributing iston b (Fig. 2) the pipe e is shut oil bythe two upper piston parts both from the pressure liquid duct 0 and alsofrom the outflow duct (1. In the bottom end position of the distributingpiston b (Fig. 3) the feed duct ais in communication with the duct e byway of the upper free cylinder space, while the middle part of thepiston separates the duct 6, e from the outflow opening (1.

At the upper end of the housing a a small cylinder 7 is fixed in thebore of WhlCl'l a freely suspended plunger piston g is guided, thebottom end of which projects from the cylinder and is made so long thatin its lower end position it is in contact with the free end b of thedistributing piston b which is in its middle position (Fig. 2).

In a separate housing It connected up to the pressure duct 0 two boresh, h are provided in each of which a piston z, k is guided. The pistons11 and k are connected with each other by a rod gear 27 k, in suchmanner that when the hand lever n is shifted they perform a The bores hand k are in communication with the pressure duct 0 and with each otherby a transverse bore h.

The bore h is in communication by a duct 0 with the space above theplunger piston g andthe bore h by a duct 7; with the space below thedistributing piston 'b. "The position of the connections 0 and p to thehousing It is so selected that in the middle position of the hand levern and the pistons 11 and is both connections are directly above theplston. v In the position of the hand lever n according to Fig. 1 thespaces below and above the er piston surface th distributing piston bare in communication above the plunger then terminates beneath thepiston i so that'the water displaced by the upward forced plunger 03 hasbeen able to escapefthrough the bore h. The pressure duct is separatedby the, piston b from the I duct e.

piston is to be actuated,

If now the workin the-hand leve'r'n is s ifted overinto its'positionaccording to Fig. 3. In doing this the piston 11 islowered The spaceabove the lunger g is thus brought into communication y way of the duct0 and the bores i h h with the pressure duct 0 so that the plunger isforced, into its bottom end position. In doing this it pushes the dis}tributing piston bin front of it.v At the same time, however,- the spacebelow the distributingpiston b has'been put into communication by way ofthe duct p with thefree space beneath thepiston k-so that the waterlying beneath the piston 12 flows out and the pressure liquid enteringthrough the duct 0 above the piston?) forces this piston into'the bottomend position shown in Fig. 3. The working cylinder nowre'ceives waterunder pressure from the duct 0 by way of the space above the upper partof the piston 12 and the duct connected up to e.

If now the working piston is suddenly to be stopped ,in' the positionreached, the hand lever 11. is moved over into its position according toFig. 2 in which the two'pistons i and k occupy their central position.The pressure means now passes byway of the duct 7) below the piston bwhich in this process is raised until it strikes against the plunger gwhichis also still under pressure and is held fixed in its bottom endposition. In this position of the distributingpiston b the duct e, aleading to the working cylinder is shut oflf b the two upper parts ofthe piston b so that the working piston mus'tremain immovable.

In order to secure the effect as described the piston iace of theplunger 9 is made somewhat greater than the difference of the activefacesof the piston 12. b

Instead of a plunger piston g a simple piston may also operate in thecylinder f projecting downwards from the cylinder by means of a pistonrod. Furthermore the aux- .iliary distribution gear h,z',killustratedmay while the piston it rises.

which plate there is the mould u and a top back support a. r s, t is apressure converter which converts the existing liquid pressure into highpressure. The pressure duct 6 leading to the press is connected by abranch (plunger) 9 and by a second branch 6 with the hollow piston t ofthe small cylinder 8 of (the pressure converter the large cylinder r ofwhich is connected bya duct 9 with the side a with the space;; abovetheauxiliary piston I of the'handcontrolled device in which the piston zoperates. The cylinder 0 of the brick eject-or device is connected by aduct 00 with a separate distributing (control) gear not shown. r

The operation of this arrangement is as follows? In Fig. 4 thedistributing gear is shown in the position of rest. The hand lever n isin its middle position and-the pressure liquid flows from the duct c byway of p be Y off the the pressure duct 0. From the large away out ofthe press'throu h the pipe (duct)] 6, e d. As soon as the wor ing pistonof the press u-h'as reached its bottom end position neath thepiston bwhich it holds in its upper end position. The piston I therefore shutson cylinder r of the pressure converter the Water 7 flows away throughthe duct g; the smallcyl' inder'ssinks and a part of the water flows outthe plate u can be swung round the-pillar u? until the mould u isbeneath the ejector press, the piston of which is actuated by a separatedistributing gear,and ejects the brick. Lastly the plate a after thefilling of the mould u is again swung" back into shown on the drawing.

If now the lever n is shifted into its position according to Fig. 5 thewaterflying below the piston 12 can flow out through the duct p;thedistributing' Piston]; istherefore forced bythe pressure i quid intoits position shown in Fig; 5. The pressure liquid can; now ass from theduct 0 into the duct e and from tiiere into the press a which-nowpresses the brick y. against the top back support to with the pressureexisting in'the main duct for example 50 atmospheres.

If then the hand lever be shifted back into its position according toFig. 4 then the pressure liquid passes out of the duct 0 by way oif-theduct fp once again beneath the piston b which is then again raised; ashowever the the position water under pressure can only fiow away-out ofthe pressu'andthe duct 6 when the distributing piston 6 reaches itsupper-end position, therefore the plunger 9 isa'lso still under pressureduring the upward movement of the piston b. The distributing piston cantherefore only be raised to beneath the plunger 9 and must consequentlynow remain in the middle position .(Fig. 6).

If the hand lever n is thereupon further put into its position accordingto Fig. 6, the bottom face of the piston 72 remains under pressure. Thewater under pressure now also flows through the duct 9 into the bigcylinder 1 of the pressure converter and drives upward the smallcylinder 8 from the piston t of which the Water under pressure, with apressure corresponding to the conversion, for example 300 atmospheresreaches the press u and the cylinder fby way of the duct 6 The plunger gis therefore now held in its bottom end position by the high pressureand the distributing piston continues immovable in the middle positionaccording to Fig. 6 in which it keeps the duct 6 shut off, so that thehigh pressure water cannot reach the low pressure duct 0.

As soon as the hand lever n is again shifted back into its positionaccording to Fig. 4 the pressure in the ducts e, e and q disappears andthe water again flows away out of the press at and the large cylinder1'.

It is straightway evident that the hand lever n must be shifted from itsposition of rest according to Fig. 4 in the first place into the lowpressure working position according to Fig. 5, and only then, by way ofthe position of rest, into the high pressure position according to Fig.6, if the press is to work with the high pressure. Therefore in eachcase preliminary pressing is done with low pressure.

I claim 1. In a distributing gear for big hydraulic working machines incombination: a .hydraulically actuated piston valve; hand controlledmeans to operate said piston valve; an auxiliary piston serving to holdsaid piston valve in a middle position; said auxiliary piston projectingby its free end into the path of the piston valve; and the cross sectionof said auxiliary piston being somewhat larger than the difierence ofthe active faces of said piston valve. I

2. In a distributing gear for big hydraulic working machines incombination: a hydraulically actuated piston valve; a hand controlleddevice to operate said piston valve; an auxiliary piston serving to holdsaid p1ston valve in a middle position; said auxiliary piston projectingby its free end into the path of said piston valve; and one side only ofsaid auxiliary piston being controlled by pressure means.

3. In a distributing gear for big hydraulic Working machines incombination: a hydraulically actuated piston valve; a hand controlleddevice to operate said piston valve; an auxiliary piston serving to holdsaid piston valve in a middle osition; said auxiliary piston projectingy its free end into the path of said piston valve; a pressure ductleading from the housing of said piston valve to the machine; means foractuating the machine by liquids of different pressure; a high pressureduct connected up to said pressure duct; and a duct connecting the spaceabove the said auxiliary piston up to the said pressure duct.

4. In a distributing gear for big hydraulic working machines incombination: a hydraulically actuated piston valve; a hand controlleddevice to operate said piston valve; an auxiliary piston serving to holdsaid piston valve in a middle position; said auxiliary piston projectingby its free end into the path of said piston valve; a pressure ductleading from the housing of said piston valve to the machine; means foractuating the machine by liquids of different pressure; a high pressureduct connected up to said pressure duct; and a duct connecting the spaceabove the said auxiliary piston up to the said pressure duct, saidpiston valve shutting off said Sigh pressure duct from said low pressureuct.

5. In a distributing gear for big hydraulic working machines incombination: a hydraulically actuated piston valve; a hand controlleddevice to operate said piston valve and adapted to be shifted into threeoperative positions; an auxiliary piston serving to hold said pistonvalve in a middle position; means for actuating the machine by liquidsof different pressure; a low pressure duct leading to the housing ofsaid piston valve and to the hand controlled device; and said handcontrolled device bein connected in such manner with the spaceieneathsaid piston valve and with a pressure converter, that inone position ofthe hand lever only the housing of said piston valve, but inthe secondsaid pressure converter also receives low pres sure, while in a thirdposition both are shut off from said pressure duct.

In witness whereof I have hereunto set my hand.

EMIL SCHGTTLER.

